1. Field of the Invention
This invention relates or pertains to a commercially practical procedure and apparatus for recovering the metal and particularly, the base metal content of wire scrap which is to be salvaged. A phase of the invention deals with a critically controlled procedure for recovering the base metal content of metal coated scrap wire in a substantially clean and bright condition, and optionally with recovery of the coating metal after it has been stripped from the base metal.
2. Description of the Prior Art
Various approaches have been attempted in the recovery of insulated electric wire scrap, but none have been commercially practical or capable of a continuous, fully integrated operation, and which will enable the base metal to be substantially fully recovered and in the form of substantially pure, non-oxidized bright metal. In endeavoring to find a solution to the problem presented, it should be noted that it involves the presence of an adherent, enclosing insulation of resin material, and of a molecular-like adherence of a metal coating under the resin coating and about the base metal.
One investigator endeavored to make use of the insulation in burning the aggregate, but this involves an ecological air pollution problem from the standpoint of a typical resin, such as PVC (polyvinylchloride) or polyethylene. Removal may be relatively simple where the scrap wire merely involves a non-ferrous base metal wire having a resin coating, but becomes very complicated where, as usually, the base metal wire is coated with another non-ferrous metal, such as with lead, tin or alloy thereof. In this situation, the factor of effectively, fully removing the metal coating without wasting or damaging the base or core metal, such as of copper or aluminum must be met. The need has been for the provision of an integrated, continuous, as distinguished from an uneconomical batch type of system or procedure, for efficiently and effectively, in a commercial, high production manner, accomplishing the desired results. The batch type of procedure that has heretofore been necessary mitigates against a commercial cost-to-return practicability of attempting to recover the metal content of scrap wire.